BOSTON/NEW YORK, Feb 10 (Reuters) - The U.S. Northeaststarted digging itself out of a blizzard that dumped up to 40inches of snow with hurricane force winds, killing at least ninepeople and leaving about half a million customers without power.

Airports slowly cranked back to life on Sunday, rare travelbans in Connecticut and Massachusetts were lifted, but roadsthroughout the region remained treacherous, according to statetransportation departments.

As the region recovered, another large winter storm buildingacross the Northern Plains was expected to leave a foot of snowand bring high winds from Colorado to central Minnesota intoMonday, the National Weather Service said.

South Dakota was expected to be hardest hit, with windsreaching 50 miles per hour, creating white-out conditions. Thestorm was expected to reach parts of Nebraska, North Dakota,Wyoming and Wisconsin.

Friday and Saturday's mammoth storm stretched from the GreatLakes to the Atlantic and covered several spots in the Northeastwith more than 3 feet (90 cm) of snow. Connecticut, Rhode Islandand Massachusetts took the brunt of the blizzard.

Hamden, Connecticut, had 40 inches and nearby Milford 38inches, the National Weather Service said.

Amtrak said it planned to run a limited service between NewYork and Boston on Sunday and a regular Sunday schedule from NewYork to the state capital in Albany.

However, the Massachusetts Bay Transportation Authority, theRhode Island Public Transit Authority and Connecticut Transitsaid service would remain suspended Sunday.

Stratford, Connecticut, Mayor John Harkins told WTNHtelevision on Saturday snow had fallen at a rate of 6 inches anhour and even plows were getting stuck.

The storm dropped 31.9 inches (81 cm) of snow on Portland,Maine, breaking a 1979 record, the weather service said. Windsgusted to 83 miles per hour (134 km per hour) at Cuttyhunk, NewYork, and brought down trees across the region.

The storm contributed to at least five deaths in Connecticutand two each in New York state and Boston, authorities said. Amotorist in New Hampshire also died when he went off a road, butauthorities said his health may have been a factor in the crash.

The two deaths in Boston were separate incidents of carbonmonoxide poisoning in cars, an 11-year-old boy and a man in hisearly 20s. The boy had climbed into the family car to keep warmwhile his father cleared snow. The engine was running but theexhaust was blocked, said authorities.

There were also road rescues along the Long IslandExpressway from Friday night to Saturday morning, some usingsnowmobiles. A baby girl was delivered early Saturday byemergency services personnel in Worcester, Massachusetts.

About 5,800 flights were canceled Friday and Saturday,according to Flightaware, a flight tracking service. Boston'sLogan International Airport reopened late on Saturday, accordingto the Federal Aviation Administration.

Bradley International Airport in Windsor Locks, Connecticut,and Long Island MacArthur Airport were both expected to reopenon Sunday morning. Both were closed on Saturday.

By early Sunday, utility companies were reporting roughly500,000 customers still without electricity across the ninestate region after the wet heavy snow brought down tree branchesand power lines. About 277,000 were in Massachusetts.

(Additional reporting by Brendan O'Brien in Wisconsin, ScottMalone in Boston, Kevin Gray in Miami, Ellen Wulfhorst in NewYork, Ian Simpson in Washington, Jason McLure in Maine, DanBurns in Connecticut, and Dan Lovering and Zach Howard inMassachusetts; Writing by David Bailey; Editing by AndrewHeavens)